Aldo Leopold Legacy Center
Materials Make the Building
Locally-Harvested Lumber
The pine trees Aldo Leopold and his family planted in 1935-1948 are a major building component in the Legacy Center. In the form of structural columns, beams, and trusses, as well as interior paneling and finish work, Leopold lumber is featured in all three of the Legacy Center buildings.
Two harvests on the Leopold Memorial Reserve produced approximately 90,000 board feet of lumber for the Legacy Center. Certified by the Forest Stewardship Council through the Community Forestry Resource Center, this material had a market value conservatively estimated at $250,000—more than 70 percent of the value of the total lumber used in construction. Structural materials for columns, beams, and trusses was milled on site, while Samsel’s Ltd., a family-owned sawmill located 70 miles away, milled 65,000 board feet for siding, wall paneling, and other finish material.
Innovative trusses are built from Leopold logs left in the round. These roundwood trusses allowed the architects to design using materials that would usually be considered “substandard” for structural purposes. The logs forming the trusses are of small diameter — between 6” and 8” —that could not be milled into load-bearing square beams. However, by keeping the logs in the round, the sapwood, the strongest part of the wood, is retained, and in the truss formation these logs are incredibly strong. In fact, they are strong enough that they can span the roof of a 30’ deep building without any internal support columns.
When the Leopold lumber could not provide material for square roof rafters, this element of the main building was re-designed to incorporate roundwood rafters. If the rafters had been purchased, they would have been Douglas fir trucked from the West Coast. The smaller diameter logs were on site, locally harvested, and planted by Leopold.
Other locally harvested wood has been used extensively for exterior siding, flooring, furniture, and interior paneling. The remaining building materials, where possible, are comprised of recycled aluminum, reused wood, reclaimed stone, and rapidly renewable materials.
Strengthening our ‘Shell’
To reduce leakage to the outdoors, significant investments have been made in the building envelope. Some of these investments have been relatively standard upgrades to insulation of higher R-values (the measure of a material’s resistance to heat flow), while other investments have been more innovative.
Using structural insulated panels (SIPs) in place of frame construction has been particularly important in increasing the overall R-value of walls. SIPs are composed of a thick layer of Styrofoam sandwiched in between two sheets of fiber board. They often have have locking mechanisms to connect the panels to each other very tightly, decreasing air infiltration. They also provide a continuous insulation layer in the wall, unlike in framed walls where each stud causes a gap in insulation.
Windows were selected for their insulating properties and lower solar heat gain coefficients. As a result, the R-values for almost every part of the building envelope are at least twice the values required by state code.
Reusing Materials
Beyond using local raw materials, the design team was able to reuse stone from a previous structure in the Legacy Center as well. The beautiful stormwater aqueduct and foyer fireplace are faced with reused Dane County Limestone, a very soft limestone with some of the properties of sandstone. The stone was reclaimed from an airplane hanger built by the Civilian Conservation Corps in the 1930’s at the Dane County Regional Airport. This hanger was torn down to expand the airport. Monona Masonry reclaimed the stone and was able to use it in the Legacy Center fireplace.